RECOMMENDED STRIP SIZE. 2 x X25-M 160 GB G2 RAID 0

[asalcedo]

I need to know what is the best strip (stripe) size for my 2x X25-M 160 GB G2 Raid 0 on my Dell laptop M6500.

The laptop will be used for general web browsing, Microsoft Office, Photoshop, Visual Studio and other smaller programs.

I tried 64 kb based on some research that I read some time ago. Then I read that 128 kb was better. I tried that and the boot up times were substantially better than with 64 kb. Which makes sense. Because booting up implies, I believe, large sequential reads, which are performed faster if the strips are of larger size.

Now I read in the Intel Rapid Storage Technology Help that the default Strip size is 16 kB for Solid state disks, which seems to imply that 16 kB is the recommended one.



Thanks,

Antonio

 

[corkyg]

Please define what you mean by "strip." Are you referring to cache memory used with a SSD?

 

[vol7ron]

Please define what you mean by "strip." Are you referring to cache memory used with a SSD?

I think he means stripe size, since he said Raid-0.

At first, what I thought is that you'd want smaller, but from what I've read, for SSDs, 64KB was still the default. Testing is going to be the ultimate decision maker - I know you don't want to do that, but each setup is different. What some people mentioned was that the larger, the better (128KB and up) depending on the controller.

http://www.storagereview.com/guide/perfStripe.html

 

[corkyg]

OK - there's a big difference between strips and stripes.

Your answer makes some sense.

 

[asalcedo]

I think he means stripe size, since he said Raid-0.

At first, what I thought is that you'd want smaller, but from what I've read, for SSDs, 64KB was still the default. Testing is going to be the ultimate decision maker - I know you don't want to do that, but each setup is different. What some people mentioned was that the larger, the better (128KB and up) depending on the controller.

http://www.storagereview.com/guide/perfStripe.html

Hi, yes I mean stripe. I used "strip" because that is what Intel uses in its documentation.

I will ultimately may have to do some testing, it looks like the only way to know for sure, but I would rather leave that to the labs or at least have a starting point of reference (16kB versus 64kb or 128kb) is too much of a variation, which implies too much testing.

I do know that 128kB for me was better than 64kB. I don't know if linearity is applicable here, which would imply that 16kB is out of the question, but is precisely what Intel recommends.

The link does not address SSDs, which may behave differently.

Someone must have studied and tested this already. ... but I have not found it..

 

[Spikesoldier]

for SSD raid 0, intel recommends a 16KB data strip size.

 

[Elganja]

I tried 32, 64 and 128 (128 was the largest allowed by the intel controller) ... 128 yielded the best benchmark results for me (for reading)...

2 x Intel X25-V 40GB in Raid 0, 128k Stripe Size, and 60GB of of allocated space (My OS drive)

http://img844.imageshack.us/img844/771/ssd1.png

2 x Intel X25-M G2 160GB in Raid 0, 128k Stripe Size, and 250 GB of of allocated space (My Games drive)

http://img842.imageshack.us/img842/4948/ssd2.png

 

[asalcedo]

Hello Elganja,

Thank you very much for your inputs.

They actually coincide with my experience. For me 128 kB (also the largest allowed by my Intel controller) cut boot up time from 29s (for 64 kB) to 26s. Applications did also launch more quickly.

The 128 kB was on a slightly cleaner drive (only a few programs and services loading) but the improvement was still significant.

I did not do testing of random read/write of small blocks.

Still, as Spikesoldier says, the recommendation by Intel is 16kB.

Has anybody tried 16kB and compared?

Thanks,

Antonio

 

[asalcedo]

Well, I still find it difficult to understand why this issue is not clearly answered.

Anyway, I have now tried 16 kB and 128 kB.

128 kB has given me better results in booting up and launching applications.

I have then decided to use 128 kB stripe size.

Antonio

 

[Makaveli]

Hello Elganja,

Thank you very much for your inputs.

They actually coincide with my experience. For me 128 kB (also the largest allowed by my Intel controller) cut boot up time from 29s (for 64 kB) to 26s. Applications did also launch more quickly.

The 128 kB was on a slightly cleaner drive (only a few programs and services loading) but the improvement was still significant.

I did not do testing of random read/write of small blocks.

Still, as Spikesoldier says, the recommendation by Intel is 16kB.

Has anybody tried 16kB and compared?

Thanks,

Antonio

Did you really see a difference in application launch speed when its SSD vs SSD Raid 0?

Wouldn't the access time not change at all since Raid 0 does nothing for it.

 

[asalcedo]

Access times my be the same in Raid 0 but read and writes are almost double. I have not compared but the speed difference is so large that I think there is no question that is is faster for almost everything.

Pleople talk about Raid overhead, loss of Trim, but still.

 

[Sunburn74]

for SSD raid 0, intel recommends a 16KB data strip size.

What source are you getting that from BTW? .

 

[Spikesoldier]

What source are you getting that from BTW? .

from intel's rapid storage technology application.